add some logging, build for jdk 11

Author: osheroff

pom.xml

@@ -105,8 +105,7 @@
                 <artifactId>maven-compiler-plugin</artifactId>
                 <version>3.5.1</version>
                 <configuration>
-                    <source>1.8</source>
-                    <target>1.8</target>
+                    <release>11</release>
                 </configuration>
             </plugin>
             <plugin>

src/main/java/com/github/shyiko/mysql/binlog/network/HostnameChecker.java

@@ -61,6 +61,8 @@
 import java.util.List;
 import java.util.NoSuchElementException;
 import java.util.TreeSet;
+import java.util.logging.Level;
+import java.util.logging.Logger;
 
 /**
  * Interface for checking if a hostname matches the names stored inside the
@@ -221,6 +223,8 @@ public final void check(final String[] host, final String[] cns,
         };
 
     abstract class AbstractChecker implements HostnameChecker {
+        private final Logger logger = Logger.getLogger(getClass().getName());
+
         public static String[] getCNs(X509Certificate cert) {
             try {
                 final String subjectPrincipal = cert.getSubjectX500Principal().getName(X500Principal.RFC2253);
@@ -406,10 +410,19 @@ is presenting (e.g. edit "/etc/apache2/server.crt"
             check(host, x509);
         }
 
+        private String commaJoin(String [] input) {
+            if ( input == null ) return "";
+            return String.join(",", Arrays.asList(input));
+        }
+
         public void check(String[] host, X509Certificate cert)
             throws SSLException {
             String[] cns = AbstractChecker.getCNs(cert);
             String[] subjectAlts = AbstractChecker.getDNSSubjectAlts(cert);
+            logger.log(Level.INFO,
+                "attempting to verify SSL identity '" + commaJoin(host) + "' " +
+                    "against cns: [" + commaJoin(cns) + "], " +
+                    "subject-alts: [" + commaJoin(subjectAlts) + "]");
             check(host, cns, subjectAlts);
         }